Electric valve

ABSTRACT

An electric valve, including a valve body part, a valve seat part, and a valve core part. The valve core part is provided in an inner cavity of the valve body part. The valve core part comprises a valve core. The valve core comprises a lower segment portion. The valve base part comprises a first sealing portion. An end of the lower segment portion can be abutted against or separated from the first sealing portion. The valve body part comprises a bushing part. The valve core part comprises a second sealing portion. The diameter D1 of the axial projection loop of the outer edge of the second sealing portion on the cross section of the lower segment portion, the outer diameter D2 of the lower segment portion, and the inner diameter D3 of the lower segment portion, satisfy: 0.2 mm2≤D1*(D2−D3)≤6 mm2.

CROSS-REFERENCED APPLICATIONS

This application is the national phase of international patentapplication PCT/CN2020/082916, titled “ELECTRIC VALVE”, filed on Apr. 2,2020, which claims the benefit of priorities to the following twoChinese patent applications, both of which are incorporated herein byreference in their entireties,

-   -   1) Chinese Patent Application No. 201910260394.7, titled        “ELECTRIC VALVE”, filed with the China National Intellectual        Property Administration on Apr. 2, 2019; and    -   2) Chinese Patent Application No. 201910381370.7, titled        “ELECTRIC VALVE”, filed with the China National Intellectual        Property Administration on May 8, 2019.

BACKGROUND 1. Field of the Disclosure

The present application relates to the technical field of fluid control,and in particular to an electric valve.

2. Discussion of the Background Art

FIG. 11 is a schematic diagram of a partial structure of an electricvalve in the background technology. The electric valve as shown in FIG.11 includes a valve seat 01, a fluid inlet 02 and a fluid outlet 03. Thevalve seat 01 includes a valve port portion 011, a valve core 04 canaxially move to abut against or separate from the valve port portion 011to close or open a valve port 012 of the electric valve. How to reducethe internal leakage when the electric valve is closed is a technicalproblem that those skilled in the art are constantly trying to solve.

SUMMARY

An object of the present disclosure is to provide an electric valve,which has reduced internal leakage when the electric valve is closed.

The electric valve according to the present disclosure includes a valvebody component, a valve seat component, and a valve core componentarranged in an inner chamber of the valve body component. The valve corecomponent includes a valve core, the valve core is substantiallytubular, the valve core includes a body portion and a lower section, andthe lower section is substantially annular. The lower section has asubstantially uniform outer diameter and a substantially uniform innerdiameter. The valve seat component includes a first sealing portion, andan end of the lower section is configured to abut against or separatefrom the first sealing portion. The valve body component includes abushing component. The valve core component includes a second sealingportion, the valve core component is in sliding fit with the bushingcomponent through the second sealing portion, and the second sealingportion abuts against an inner wall of the bushing component. The innerchamber includes a first chamber located above the valve core component,the valve core component includes an equalizing flow path, and when thelower section is abutted against the first sealing portion, the firstchamber is communicated with a first fluid port of the electric valvethrough the equalizing flow path. An axial projection circular line ofan outer edge of the second sealing portion on the cross section of thelower section has a diameter D1. The lower section has an outer diameterD2 and an inner diameter D3. D1, D2, and D3 satisfy the followingrelationship: 0.2 mm²≤D1*(D2−D3)≤6 mm².

In the electric valve provided by the present application, the lowersection is substantially annular, the lower section has thesubstantially uniform outer diameter and the substantially uniform innerdiameter, the valve core component includes the second sealing portion,the axial projection circular line of the outer edge of the secondsealing portion on the lower section has the diameter D1, and the lowersection has the outer diameter D2 and the inner diameter D3. D1, D2, andD3 satisfy: 0.2 mm²≤D1*(D2−D3)≤6 mm², so as to reduce the internalleakage of the electric valve when the valve is closed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structural view of an electric valve in a closedstate provided according to the present disclosure;

FIG. 2 is a partially enlarged view of portion I1 in FIG. 1 ;

FIG. 3 is a schematic structural view of the valve core in FIG. 1 ;

FIG. 4A is a partially enlarged view of portion I2 in FIG. 3 ;

FIG. 4B is a schematic structural view of a first modified example atportion I2 in FIG. 3 ;

FIG. 4C is a schematic structural view of a second modified example atportion I2 in FIG. 3 ;

FIG. 4D is a schematic structural view of a third modified example atportion I2 in FIG. 3 ;

FIG. 5A is a schematic diagram of the force analysis of the valve corecomponent when the fluid enters in a forward direction;

FIG. 5B is a schematic diagram of the force analysis of the valve corecomponent when the fluid enters in a reverse direction;

FIG. 6 is a schematic structural view of the electric valve providedaccording to the second embodiment of the present disclosure;

FIG. 7 is a partial schematic structural view of FIG. 6 ;

FIG. 8 is a schematic structural view of the valve core in FIG. 6 ;

FIG. 9 is a schematic structural view of the electric valve providedaccording to the third embodiment of the present disclosure;

FIG. 10 is a partial schematic structural view of the electric valve inFIG. 9 ; and

FIG. 11 is a schematic diagram of a partial structure of an electricvalve in the background technology.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In order to enable those skilled in the art to better understand thetechnical solutions of the present disclosure, the present disclosurewill be further described in detail with reference to the drawings andspecific embodiments.

It should be noted here that, the orientation terms, such as up anddown, involved in this application are defined with the components beinglocated at the positions shown in the drawings of the application, whichare only for clarity and ease of description of the technical solutions.It will be appreciated that, those orientation terms used herein shouldnot limit the protection scope of the present application.

The “fixedly connected” herein refers to that two components may bedirectly fixedly connected, or two components may be fixedly connectedby other components, that is, two components are indirectly fixedlyconnected.

FIG. 1 is a schematic structural view of an electric valve according tothe first embodiment of the present disclosure. FIG. 2 is a partiallyenlarged view of portion I1 in FIG. 1 . FIG. 3 is a schematic structuralview of the valve core in FIG. 1 . FIG. 4A is a partially enlarged viewof portion I2 in FIG. 3 .

As shown in FIGS. 1 to 3 , FIGS. 4A, 4B, 4C and 4D, the electric valveincludes a valve body component 10, a valve seat component 20, a valvecore component 30, and a sealing assembly. The valve body component 10includes a valve body 11, and a second fluid port A is defined on thevalve body 11. The valve seat component 20 includes a valve seat 21 anda sealing ring 22, and a first fluid port B is defined on the valve seat21. The valve core component 30 is disposed in an inner chamber of thevalve body component 10, and the valve core component 30 includes avalve core 31, and the valve core 31 is substantially tubular. The valvecore 31 includes a circular lower section 311 (which here not onlyrefers to a ring with an absolute uniform outer diameter and an absoluteuniform inner diameter, also refers to a ring with a little irregularitydue to such as tolerance), the inner diameter of the lower section 311is set to be substantially uniform, and the outer diameter of the lowersection 311 is set to be substantially uniform. The sealing ring 22includes a first sealing portion 221, and an end of the lower section311 is configured to abut against or separate from the first sealingportion 221 to allow the second fluid port A to be communicated with thefirst fluid port B or not. The valve body component 10 further includesa bushing component 12, the valve core component 30 includes a secondsealing portion 321, the valve core 31 is in sliding fit with thebushing component 12 through the second sealing portion 321, and thesecond sealing portion 321 abuts against an inner wall of the bushingcomponent 12. The inner chamber of the valve body component 10 includesa first chamber 50 located above the valve core component 30. The valvecore component 30 includes an equalizing flow path E. When the valvecore 31 is abutted against the sealing ring 22, the first chamber 50 isnot communicated with the second fluid port A, and the first chamber 50is communicated with the first fluid port B through the equalizing flowpath E. With reference to the drawings, it can be understood that such adesign is beneficial to the force balance of the valve core component30.

Specifically, as shown in FIG. 3 , the valve core 31 includes a bodyportion 312, and the body portion 312 of the valve core 31 includes asmall-diameter section 3121 and a large-diameter section 3122, that is,an outer diameter of the large-diameter section 3122 is greater than anouter diameter of the small-diameter section 3121. The bushing component12 includes a bushing 121, an outer wall of the bushing 121 is fixed tothe valve body component 10 by welding, the bushing 121 includes a firsttubular portion 1211 which is substantially tubular, and the firsttubular portion 1211 has a substantially uniform inner diameter. Thevalve core component 30 further includes the sealing assembly, and thesealing assembly is abutted between an outer wall of the small-diametersection 3121 and an inner wall of the first tubular portion 1211.Specifically, the sealing assembly includes a sealing ring 35 and agasket 36. The large-diameter section 3122 of the body portion 312 isslidable relative to the inner wall of the first tubular portion 1211.The sealing ring 35 is arranged between the gasket 36 and thesmall-diameter section 3121, an inner wall of the sealing ring 35 isabutted against the outer wall of the small-diameter section 3121, andan outer wall of the gasket 36 is abutted against the inner wall of thefirst tubular portion 1211, so as to form a dynamic seal between thevalve core 31 and the bushing component 12. The dynamic seal means that,the sealing assembly is slidable relative to the bushing 121, and thesealing assembly also forms a seal between the valve core component 30and the bushing 121, that is, the side above the sealing assembly andthe side below the sealing assembly are not communicated at thislocation. The gasket 36 includes the second sealing portion 321. Anaxial projection circular line of an outer edge of the second sealingportion 321 on the lower section 311 has a diameter D1. In thisembodiment, the inner diameter of the first tubular portion 1211 is D1.The lower section 311 has an outer diameter D2 and an inner diameter D3.The diameter D1 of the axial projection circular line of the outer edgeof the second sealing portion 321 on the lower section 311, the outerdiameter D2 of the lower section 311, and the inner diameter D3 of thelower section 311 satisfy the following relationship: 1 mm²≤D1*(D2−D3)≤6mm², so as to reduce the internal leakage of the electric valve when thevalve is closed.

Since D1, D2, and D3 satisfy the relationship: D1*(D2−D3)≥1 mm², thewall of the lower section 311 may not be too thin under the conditionthat the diameter D1 of the axial projection circular line is keptunchanged, which is convenient for processing. On the other hand, thestrength reliability of the valve core 31 is acceptable, and the sealingreliability is acceptable. Furthermore, when the valve core 31 isabutted against the sealing ring 22 described below to close the valve,if the sealing ring 22 is made of a soft material, such as a rubbermaterial, such design reduces the risk that the lower section 311exceeds the material bearing limit of the sealing ring 22, reduces theimpact of the lower section 311 of the valve core 31 on the sealing ring22, and is beneficial to extending the service life of the sealing ring,so that the valve core 31 is better matched with the sealing ring 22,which reduces the internal leakage when the electric valve is closed,and is beneficial to the closing reliability of the electric valve.

The range of the formula D1*(D2−D3) is given above, and the lower limitof the range is 1 mm². It is understandable that the lower limit of theformula D1*(D2−D3) may be adjusted according to the material of thesealing ring 22. Under the premise that the sealing ring 22 is made of asoft material, if the hardness of the material is relatively high, thelower limit may be adjusted to be relatively smaller, and the range ofthe formula D1*(D2−D3) becomes larger; if the hardness of the materialis relatively low, the lower limit may be adjusted to be relativelylarger, and the range of the formula D1*(D2−D3) becomes relativelysmaller. The lower limit may be adjusted to the smallest 0.2 mm², thatis, D1*(D2−D3)≥0.2 mm², which can still achieve the object of reducingthe internal leakage when the electric valve is closed. For example, ina case that the sealing ring 22 is made of a PTFE plastic, the hardnessof the PTFE plastic is higher than that of the common rubber material,so that the limit of the D1*(D2−D3) may be adjusted to 0.2 mm².

In a case that the diameter D1 of the axial projection circular line iskept unchanged, if D1*(D2−D3)≤6 mm², the opening resistance of theelectric valve is optimized, and the internal leakage is reduced whenthe electric valve is closed, which is beneficial to the reliability ofopening the electric valve. The specific configuration will be furtherdescribed in detail in the following.

Moreover, the sealing ring 22 is made of a soft material to improve thesealing performance when the electric valve is closed. Specifically, thesealing ring 22 is made of a rubber material such as nitrile rubber. Theend of the lower section 311 of the valve core 31 is configured to abutagainst or separate from the first sealing portion 221 to allow thesecond fluid port A to be communicated with the first fluid port B ornot. The “not communicated” here means that the electric valve isoccluded if there is no internal leakage. However, in the actualproduct, a little internal leakage may still exist due to process andother reasons. Therefore, one of the effects of this application is toreduce the internal leakage, and the ideal object is to eliminateinternal leakage. When the end of the lower section 311 of the valvecore 31 is abutted against the first sealing portion 221, the innerchamber of the valve body component 10 includes a second chamber 60located between the valve core 31 and the valve body component 10, thatis, the second chamber 60 refers to a space of the inner chamber of thevalve body component which is located outside the valve core componentand is not communicated with the first chamber 50. When there is nointernal leakage in the abutment between the valve core 31 and the firstsealing portion 221, the second chamber 60 is not communicated with thefirst fluid port B.

Due to the material properties of the sealing ring 22, a radialdimension of the lower section 311 of the valve core 31 is arranged tosatisfy 0.1 mm<D2−D3<0.6 mm, so that D2−D3>0.1 mm, which is convenientfor processing the valve core 31, and reduces the damage to the sealingring 22 when the lower section 311 of the valve core 31 is abuttedagainst the sealing ring 22 to close the electric valve.

The range of the formula (D2−D3) is given above, and the lower limit ofthe range is 0.1 mm. As described above, that the lower limit of theformula (D2−D3) may be adjusted according to the material of the sealingring 22. Under the premise that the sealing ring 22 is made of a softmaterial, if the hardness of the material is relatively high, the lowerlimit may be adjusted to be relatively smaller, and the range of theformula (D2−D3) becomes larger; if the hardness of the material isrelatively low, the lower limit may be adjusted to be relatively larger,and the range of the formula (D2−D3) becomes relatively smaller. Thelower limit may be adjusted to the smallest 0.05 mm, that is,(D2−D3)≥0.05 mm. For example, in a case that the sealing ring 22 is madeof a PTFE plastic, the hardness of the PTFE plastic is higher than thatof the common rubber material, so that the limit of the (D2−D3) may beadjusted to 0.05 mm.

Compared with the case of D2−D3>0.6 mm, the case of D2−D3<0.6 mm canreduce the pressure difference force on the valve core component 10, andavoid the disadvantage for the reliability of opening the electric valvecaused by the relatively thick wall of the lower section 311. Inaddition, when the valve core 31 is operated in a direction of openingthe valve to be in a small opening-degree position (for example, thevalve-opening pulse is 10% or less of the full opening pulse), the fluidis allowed to flow quickly between the lower section 311 and the sealingring 22, thereby further improving the action performance of theelectric valve. In addition, in the present embodiment, in a case thatD1=16.2 mm, and D2−D3=0.2 mm, the action performance of the electricvalve in forward and reverse directions is well guaranteed when theelectric valve is a bidirectional valve, and the service life of thesealing ring 22 is also guaranteed.

Since the sealing ring 22 is made of a soft material such as rubber, thesealing ring 22 has certain elasticity, and is elastically deformed whensubjected to an external force. The outer diameter D2 of the lowersection 311 is set to be substantially uniform, and the inner diameterD3 of the lower section 311 is set to be substantially uniform. When thevalve core 31 moves downward to abut against the first sealing portion221 to close the electric valve, in order to control the contact areabetween the lower section 311 of the valve core 31 and the sealing ring22 during the downward movement of the valve core 31, the size of thecontact area is determined by the wall thickness (that is, the value ofD2−D3) of the lower section 311. In order to prevent the reliability ofopening and closing the valve by the valve core 31 from being affectedby the change, caused by the change of the contact area, of the fluidpressure difference force received by the valve core 31, a height L ofthe lower section 311 of the valve core 31 is arranged to be equal to orgreater than 0.4 mm.

Moreover, the valve core 31 further includes a transition portion 313,and the transition portion 313 is arranged between the body portion 312and the lower section 311. In order to facilitate the control of thecontact area between the lower section 311 of the valve core 31 and thesealing ring 22, the transition portion 313 includes a first transitionsection 3131 connected with the lower section 311, a longitudinalsection of the first transition section 3131 is substantiallycone-shaped, and as shown in FIG. 4A, an inner diameter of an upper endof the first transition section 3131 is smaller than an inner diameterof a lower end of the first transition section 3131. Specifically, afirst acute angle α is formed between an inner wall of the firsttransition section 3131 and the horizontal direction. An outer diameterof the upper end of the first transition section 3131 is greater than anouter diameter of the lower end of the first transition section 3131.Specifically, a second acute angle β is formed between an outer wall ofthe first transition section 3131 and the horizontal direction. As shownin FIG. 3 , the transition portion 313 further includes a secondtransition section 3132 connected with the body portion 312, an innerdiameter of an upper end of the second transition section 3132 issmaller than an inner diameter of a lower end of the second transitionsection 3132, an outer diameter of the upper end of the secondtransition section 3132 is smaller than an outer diameter of the lowerend of the second transition section, the outer diameter of the upperend of the second transition section 3132 is greater than the innerdiameter of the lower section 311, and the outer diameter of the upperend of the second transition section 3132 is greater than the outerdiameter of the lower section 311. With such arrangement, the axialprojection circular line M of the outer edge of the second sealingportion 321 on the valve core 31 is located in the cross section of thelower section 311, which is beneficial to the force balance of the valvecore component 30. It should be noted that the “force balance” hereinrefers to an almost balance, not necessarily an absolute balance, and ifthere is a slight unbalance of force, it can be adjusted by properlychanging the force of the driving component of the electric valve.

The lower end of the longitudinal section of the lower section 311 ofthe valve core 31 is substantially arc-shaped, so as to reduce the wearof the sealing ring 22 from the valve core 31 and improve the servicelife of the sealing ring 22. It should be noted that in this solution,the lower end surface of the valve core 31 may not be arc-shaped. Forexample, the lower end surface of the valve core 31 is substantiallysmall-plane-shaped. It should be noted that, in a case that the lowerend of the longitudinal section of the lower section 311 issubstantially arc-shaped, the arc part is relatively small, the outerdiameter and the inner diameter of the whole lower section 311 arearranged to respectively have a uniform diameter, and the arc part haslittle effect on the overall structure of the lower section 311.

FIG. 4B is a schematic structural view of a first modified example ofthe valve core 31 at portion 12 in FIG. 3 . In the valve core of thisembodiment, the first transition section 3131B of the transition portion313B is different from the structure of FIG. 4A in that the outerdiameter of the first transition section 3131B is equal to the outerdiameter of the lower section 311B. FIG. 4C is a schematic structuralview of a second modified example of the valve core 31 at portion 12 inFIG. 3 . In the valve core of this embodiment, the first transitionsection 3131C of the transition portion is different from the structureof FIG. 4A in that the inner diameter of the first transition section3131C is equal to the inner diameter of the lower section 311C. Thebeneficial effects of such configuration are the same as those of thestructure of the valve core in FIG. 4A, which will not be repeated here.FIG. 4D is a schematic structural view of a third modified example atportion I2 in FIG. 3 . In the valve core of this embodiment, thetransition portion 313D only has the second transition section 3132, andthe first transition section in FIGS. 4A to 4C is not provided. However,in order to facilitate the control of the contact area between the lowersection 311D of the valve core 31 and the sealing ring 22, the length Lof the lower section 311D is relatively long, and L≥0.4 mm, to avoid thesecond transition section 3132 from pressing against the sealing ring22.

As shown in FIG. 2 , the valve seat component 20 further includes aninner bushing 25 and a pressure block 26. The valve seat 21 includes anaxial through hole 27, and at least part of the inner bushing 25 isarranged in the axial through hole 27 and fixed to the valve seat 21 bywelding. The sealing ring 22 is arranged between an outer side of theinner bushing 25 and the valve seat 21. The valve seat 21 includes afirst stepped portion 215, and an upper end of the valve seat 21 fixesthe pressure block 26 on a stepped surface of the first stepped portion215 of the valve seat 21 by crimping. A lower end surface of thepressure block 26 is opposite to an upper end surface of the sealingring 22, to further axially limit the sealing ring 22. It isunderstandable that the lower end surface of the pressure block 26 mayabut against the sealing ring 22 or not. The pressure block 26 includesa base portion 261 and a guide portion 262. An inner diameter of theguide portion 262 is greater than an inner diameter of the base portion261. When the lower section 311 is abutted against the first sealingportion 221 of the sealing ring 22, the lower section 311 of the valvecore 31 is in clearance fit with the inner bushing 25 and the baseportion 261 of the pressure block 26. The clearance fit here means thatin an ideal state, the valve core 31 is in clearance fit with the innerbushing 25 and the pressure block 26 in order to avoid interference.However, considering factors such as assembly and process, the followingundesirable situation may exist: the valve core 31 interferes with theinner bushing 25 or the pressure block 26 instead of forming clearancefit. In addition, an inner diameter of the guide portion 262 graduallyincreases from bottom to top, that is, an inner hole of the guideportion 262 gradually expands from bottom to top. In this way, the axialmovement of the valve core 31 is guided by an inner side of the guideportion, and a flow guiding space Q is formed between an outer side ofthe valve core 31 and an inner wall of the pressure block 26 when theend of the lower section 311 of the valve core 31 is abutted against thefirst sealing portion 221 of the sealing ring 22, which is beneficial tothe flow of fluid. In addition, during the axial movement of the valvecore 31 relative to the pressure block 26, the two may cooperate toadjust the flow rate, which is convenient and low in cost.

The electric valve according to the embodiments herein may be anelectric valve with a bidirectional flow function, that is, when theelectric valve is opened, the flow direction of the fluid is to flow infrom the second fluid port A and flow out from the first fluid port B(referred to as forward direction hereinafter), or when the electricvalve is opened, the flow direction of fluid is to flow in from thefirst fluid port B and flow out from the second fluid port A (referredto as reverse direction hereinafter). The electric valve of theembodiments may only allow unidirectional flow.

In the embodiment shown in FIG. 1 , when the electric valve is in theclosed state, the axial projection circular line M of the second sealingportion 321 on the valve core 31 substantially coincides with thecentral circular line of the cross section of the lower section 311.Such a design is beneficial to the force balance of the valve corecomponent 30. Moreover, when the diameter D1 of the outer edge of theaxial projection circular line M of the second sealing portion 321 onthe valve core 31 and the value of D2−D3 are known, the values of D2 andD3 can be designed conveniently and easily according to this design.

FIG. 5A is a schematic diagram of the force analysis of the valve corecomponent when the fluid enters in the forward direction, and FIG. 5B isa schematic diagram of the force analysis of the valve core componentwhen the fluid enters in the reverse direction.

As shown in FIGS. 5A and 5B, when the fluid with pressure P flows in theforward direction, the main pressure difference force on the valve corecomponent 30 is F_(forward)=Pπ(D2 ²−D1 ²) in the closed state, and theacting direction of the force is downward; when the fluid with pressureP flows in the reverse direction, the main pressure difference force onthe valve core component 30 is F_(reverse)=Pπ(D1 ²−D3 ²) in the closedstate, and the acting direction of the force is downward, which isbeneficial to the reliability of closing the valve and also beneficialto reducing the internal leakage when the electric valve is closed.

When the size of structure other than the valve core of the electricvalve is fixed, that is, when D1 is fixed, there are three followingsituations which can cause the (D2−D3) to increase: first, D2 remainsunchanged, and D3 decreases; second, D2 increases, D3 remains unchanged;and third, both D2 and D3 increase.

In a case that D2 remains unchanged and D3 decreases, F_(forward) isbasically unchanged, and F_(reverse) increases, that is, when the fluidflows in the forward direction, this case has little effect on theopening and closing actions of the electric valve; when the fluid flowsin the reverse direction, the resistance of opening the electric valveincreases, which is not beneficial to the reliability of opening theelectric valve when the fluid flows in the reverse direction, and thegreater the value of D2−D3, the greater the adverse effect.

In a case that D2 increases and D3 remains unchanged, F_(forward)increases, and F_(reverse) is basically unchanged, that is, when thefluid flows in the forward direction, the resistance of opening theelectric valve increases, which is not beneficial to the reliability ofopening the electric valve when the fluid flows in the forwarddirection, and the greater the value of D2−D3, the greater the adverseeffect; when the fluid flows in the reverse direction, this case haslittle effect on the opening and closing actions of the electric valve.

In a case that both D2 and D3 increase, F_(forward) increases, andF_(reverse) decreases, that is, when the fluid flows in the forwarddirection, the resistance of opening the electric valve increases, whichis not beneficial to the reliability of opening the electric valve whenthe fluid flows in the forward direction, and the greater the value ofD2−D3, the greater the adverse effect; when the fluid flows in thereverse direction, this case is beneficial to the opening action of theelectric valve.

Therefore, the electric valve according to this solution is designedwith 1 mm²≤D1*(D2−D3)≤6 mm², so that in a case that the electric valveis a bidirectional electric valve, the reliability of opening theelectric valve in the forward and reverse directions is controlled to anacceptable degree, while the performance of the internal leakage and thereliability of closing the electric valve are improved.

The above design is also beneficial to the serialization of products,that is, in a case that D1 is determined, the value range of D2−D3 canbe calculated through the above numerical relationship, that is, thewall thickness of the lower section 311 of the valve stem can beobtained. Similarly, in a case that the range of D2−D3 is determined,the value range of D1 can be calculated through the above numericalrelationship.

It should be noted that, on the basis of the description of theforegoing technical solutions, the electric valve according to theembodiments may be an electronic expansion valve which can regulate thefluid flow, or an on-off valve, such as a solenoid valve or abidirectional solenoid valve.

FIG. 6 is a schematic structural view of the electric valve providedaccording to the second embodiment of the present disclosure. FIG. 7 isa partial schematic structural view of FIG. 6 . FIG. 8 is a schematicstructural view of the valve core in FIG. 6 .

The difference between the electric valve in this embodiment and theelectric valve in the previous embodiment lies in that, the sealingassembly is a part of a sealing seat component, and the valve corecomponent is in sliding fit with the sealing assembly. The valve coreincludes the second sealing portion. Detailed description is givenbelow.

As shown in FIGS. 6 to 8 , the valve seat component further includes aninner bushing 25E and a pressure block 26E. A bushing component 12Eincludes a bushing 121E and a sealing assembly, and the bushing 121Eincludes a second tubular portion 1211E (only part is shown in thefigure). The sealing assembly is fixed or limited on the bushing 121E,and the sealing assembly includes a sealing ring 35E and a gasket 36E.The valve core 31E includes a body portion 312E and a lower section311E, at least part of the gasket 36E is abutted against an inner wallof the body portion 312E, and the sealing ring 35E is abutted against aninner wall of the bushing 121E. The body portion 312E is slidablerelative to the sealing assembly. The body portion 312E has asubstantially uniform outer diameter. An outer wall of the body portion312E includes a second sealing portion 321E. The diameter of an axialprojection circular line N of the outer wall of the body portion 312E onthe valve core 31E is D1. The inner diameter of the lower section 311Eof the valve core 31E is substantially uniform, and the outer diameterof the lower section 311E is substantially uniform. The outer diameterof the lower section 311E is D2, and the inner diameter of the lowersection 311E is D3. The diameter D1, the outer diameter D2 of the lowersection 311E, and the inner diameter D3 of the lower section satisfy: 1mm²≤D1*(D2−D3)≤6 mm². Other structures of this embodiment can beunderstood with reference to the first embodiment. The variousvariations and the force relationship of the lower section in the firstembodiment are also applicable to this embodiment. Accordingly, thisembodiment also has the same beneficial effects as the first embodiment,which can be understood with reference to the first embodiment and willnot be repeated here. More specifically, in this embodiment, D1=9.2 mm,D2−D3=0.5 mm. The action performance of the electric valve in forwardand reverse directions is well guaranteed when the electric valve is abidirectional valve, and the service life of the sealing ring 22 is alsoguaranteed.

FIG. 9 is a schematic structural view of the electric valve providedaccording to the third embodiment of the present disclosure. FIG. 10 isa partial schematic structural view of the electric valve in FIG. 9 .

As shown in the figure, the electric valve is specifically a solenoidvalve, which includes a plug 100 and a moving iron core 101. The plug100 and the moving iron core 101 are the components of a drivingcomponent. The valve body component 102 is fixed to the valve seatcomponent 103 by welding, and a valve core 31F includes a body portion312F and a lower section 311F. The valve seat component includes aninner bushing 25F and a pressure block 26F. In this embodiment, an outerwall of the body portion 312F is designed to have a uniform diameter,and the outer wall is used as a second sealing portion. A diameter D1 ofthe second sealing portion, an outer diameter D2 of the lower section311F, and an inner diameter D3 of the lower section 311F satisfy: 1mm²≤D1*(D2−D3)≤6 mm². The solenoid valve can also achieve the samefunction of reducing the internal leakage when the electric valve isclosed as the foregoing embodiments, and other structures of thesolenoid valve may be designed with reference to the foregoingembodiments, and the design may also be modified within the framework ofthe principle of the present application, which will not be repeatedhere.

The electric valve according to the present application is described indetail hereinbefore. The principle and the embodiments of the presentapplication are illustrated herein by specific examples. The abovedescription of examples is only intended to facilitate the understandingof the method and spirit of the present application. It should be notedthat, for those skilled in the art, many modifications and improvementsmay be made to the present disclosure without departing from theprinciple of the present disclosure, and these modifications andimprovements are also deemed to fall into the protection scope of thepresent disclosure defined by the claims.

The invention claimed is:
 1. An electric valve, comprising a valve bodycomponent, a valve seat component, and a valve core component arrangedin an inner chamber of the valve body component, wherein the valve corecomponent comprises a valve core, the valve core is substantiallytubular, the valve core comprises a body portion and a lower section,the lower section is substantially annular, and the lower section has asubstantially uniform outer diameter and a substantially uniform innerdiameter; the valve seat component comprises a first sealing portion,and an end of the lower section is configured to abut against orseparate from the first sealing portion; the valve body componentcomprises a bushing component, the valve core component comprises asecond sealing portion, the valve core component is in sliding fit withthe bushing component through the second sealing portion, and the secondsealing portion is configured to abut against an inner wall of thebushing component; the inner chamber comprises a first chamber locatedabove the valve core component, the valve core component comprises anequalizing flow path, and when the lower section is abutted against thefirst sealing portion, the first chamber is communicated with a firstfluid port of the electric valve through the equalizing flow path; anaxial projection circular line of an outer edge of the second sealingportion on a cross section of the lower section has a diameter D1, thelower section has an outer diameter D2 and an inner diameter D3; D1, D2,and D3 satisfy: 0.2 mm²≤D1*(D2−D3)≤6 mm²; the valve seat componentcomprises a sealing ring, the sealing ring is made of a soft material,the sealing ring comprises the first sealing portion, the end of thelower section is configured to abut against or separate from the firstsealing portion to allow a second fluid port of the electric valve tocommunicate with the first fluid port or not, and a height L of thelower section is equal to or greater than 0.4 mm, wherein a transitionportion is comprised between the body portion and the lower section, thetransition portion comprises a first transition section connected withthe lower section, and an outer diameter of an upper end of the firsttransition section is greater than an outer diameter of a lower end ofthe first transition section.
 2. The electric valve according to claim1, wherein the electric valve satisfies the following relationship: 0.1mm<D2−D3<0.6 mm.
 3. The electric valve according to claim 1, wherein aninner diameter of the upper end of the first transition section issmaller than an inner diameter of a lower end of the first transitionsection.
 4. The electric valve according to claim 1, wherein thetransition portion comprises a second transition section connected withthe body portion, an inner diameter of an upper end of the secondtransition section is smaller than an inner diameter of a lower end ofthe second transition section, an outer diameter of the upper end of thesecond transition section is smaller than an outer diameter of the lowerend of the second transition section, and the outer diameter of theupper end of the second transition section is greater than the innerdiameter of the lower section.
 5. The electric valve according to claim1, wherein the valve core component further comprises a sealingassembly, the bushing component comprises a first tubular portion whichis substantially tubular, the sealing assembly is abutted between anouter wall of the valve core and an inner wall of the first tubularportion, the sealing assembly comprises the second sealing portion, andthe second sealing portion is in sliding fit with the inner wall of thefirst tubular portion.
 6. The electric valve according to claim 5,wherein the sealing assembly comprises a sealing ring and a gasket, thebody portion comprises a small-diameter section and a large-diametersection, the sealing ring is arranged between the gasket and thesmall-diameter section, the gasket comprises the second sealing portion,the valve body component further comprises a valve body, the bushingcomponent comprises a bushing fixed to the valve body by welding, thebushing comprises the first tubular portion, the first tubular portionhas a substantially uniform inner diameter, and the inner wall of thefirst tubular portion has a diameter D1.
 7. The electric valve accordingto claim 5, wherein D1=16.2 mm, and D2−D3=0.2 mm.
 8. The electric valveaccording to claim 1, wherein the bushing component comprises a bushingand a sealing assembly, the valve body component further comprises avalve body, the bushing is fixed to the valve body by welding, thebushing comprises a second tubular portion, the sealing assembly isabutted between an inner wall of the second tubular portion and an outerwall of the body portion, the body portion has a substantially uniformouter diameter, and the body portion comprises the second sealingportion.
 9. The electric valve according to claim 8, wherein D1=9.2 mm,and D2−D3=0.5 mm.
 10. The electric valve according to claim 8, whereinthe sealing assembly comprises a sealing ring and a gasket, the sealingring is arranged between the gasket and the second tubular portion, andat least part of the gasket abuts against the outer wall of the bodyportion.
 11. The electric valve according to claim 1, wherein the valveseat component further comprises an inner bushing and a pressure block,the valve seat comprises an axial through hole, at least part of theinner bushing is arranged in the axial through hole, the sealing ring isarranged between an outer side of the inner bushing and the valve seat,the valve seat comprises a first stepped portion, and a lower endsurface of the pressure block is abutted against the first steppedportion and/or the sealing ring.
 12. The electric valve according toclaim 11, wherein the valve seat is fixed with the pressure block bycrimping, the pressure block comprises a base portion abutting againstthe sealing ring and a guide portion arranged above the base portion, aninner diameter of the guide portion gradually increases from bottom totop; when the end of the lower section is abutted against the sealingring, the lower section is in clearance fit with the inner bushing andthe base portion.
 13. The electric valve according to claim 1, whereinthe axial projection circular line substantially coincides with acentral circular line of the cross section of the lower section, and alower end of a longitudinal section of the lower section issubstantially arc-shaped.
 14. An electric valve, comprising a valve bodycomponent, a valve seat component, and a valve core component arrangedin an inner chamber of the valve body component, wherein the valve corecomponent comprises a valve core, the valve core is substantiallytubular, the valve core comprises a body portion and a lower section,the lower section is substantially annular, and the lower section has asubstantially uniform outer diameter and a substantially uniform innerdiameter; the valve seat component comprises a first sealing portion,and an end of the lower section is configured to abut against orseparate from the first sealing portion; the valve body componentcomprises a bushing component, the valve core component comprises asecond sealing portion, the valve core component is in sliding fit withthe bushing component through the second sealing portion, and the secondsealing portion is configured to abut against an inner wall of thebushing component; the inner chamber comprises a first chamber locatedabove the valve core component, the valve core component comprises anequalizing flow path, and when the lower section is abutted against thefirst sealing portion, the first chamber is communicated with a firstfluid port of the electric valve through the equalizing flow path; anaxial projection circular line of an outer edge of the second sealingportion on a cross section of the lower section has a diameter D1, thelower section has an outer diameter D2 and an inner diameter D3; D1, D2,and D3 satisfy: 0.2 mm²≤D1*(D2−D3)≤6 mm², wherein the valve seatcomponent further comprises an inner bushing and a pressure block, thevalve seat comprises an axial through hole, at least part of the innerbushing is arranged in the axial through hole, the sealing ring isarranged between an outer side of the inner bushing and the valve seat,the valve seat comprises a first stepped portion, and a lower endsurface of the pressure block is abutted against the first steppedportion and/or the sealing ring.
 15. The electric valve according toclaim 14, wherein the valve seat is fixed with the pressure block bycrimping, the pressure block comprises a base portion abutting againstthe sealing ring and a guide portion arranged above the base portion, aninner diameter of the guide portion gradually increases from bottom totop; when the end of the lower section is abutted against the sealingring, the lower section is in clearance fit with the inner bushing andthe base portion.
 16. The electric valve according to claim 14, whereinthe axial projection circular line substantially coincides with acentral circular line of the cross section of the lower section, and alower end of a longitudinal section of the lower section issubstantially arc-shaped.
 17. The electric valve according to claim 14,wherein the electric valve is an electronic expansion valve or asolenoid valve.
 18. The electric valve according to claim 17, whereinthe electronic expansion valve is a bidirectional electronic expansionvalve, and the solenoid valve is a bidirectional solenoid valve.